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Gennadi Naumov Elena Naumova Hilkka Turakainen Pirkko Suominen Matti Korhola 《Current genetics》1991,20(4):269-276
Summary We used a combination of genetic hybridization analysis and electrokaryotyping with radioactively labelled MEL1 gene probe hybridization to isolate and identify seven polymeric genes for the fermentation of melibiose in strain CBS 5378 of Saccharomyces cerevisiae (syn. norbensis). Four of the MEL genes, i.e. MEL3, MEL4, MEL6 and MEL7, were allelic to those found in S. cerevisiae strain CBS 4411 (syn. S. oleaginosus) whereas three genes, i.e. MEL8, MEL9 and MEL10 occupied new loci. Electrokaryotyping showed that all seven MEL genes in CBS 5378 were located on different chromosomes. The new MEL8, MEL9 and MEL10 genes were found on chromosomes XV, X/XIV and XII, respectively. 相似文献
3.
Anatomical examinations (33 cadavers) for studying parasympathetic innervation of the upper abdominal organs formed the basis for developing a new variant of proximal gastric vagotomy--anterior seromyotomy of the body and fundus of the stomach in combination with posterior truncal or posterior selective vagotomy. This variant excludes mobilization of the esophagus and makes it possible to preserve the ligament apparatus of the esophago-gastric junction as well as the parasympathetic innervation of the pancreas, small and large intestine, kidneys, and adrenals, which may be a measure for the prevention of some ++post-vagotomy complications. 相似文献
4.
Functional characterization of peripheral blood lymphocytes in chronic HBsAg carriers 总被引:3,自引:3,他引:3
G J Alexander M Mondelli N V Naumov K T Nouriaria D Vergani D Lowe A L Eddleston R Williams 《Clinical and experimental immunology》1986,63(3):498-507
Increased proportions of suppressor/cytotoxic T cells have been identified in the peripheral blood of chronic HBsAg carriers and to investigate a possible relationship to T cell cytotoxicity against autologous hepatocytes, suppressor cell activity, viral replication and the histological type of disease, 42 consecutive HBsAg carriers undergoing a liver biopsy have been investigated. The proportion of suppressor/cytotoxic lymphocytes directly correlated with T cell cytotoxicity to autologous hepatocytes and both were higher in those with HBeAg in serum than in those with anti-HBe or those on corticosteroid therapy. There was no relationship to underlying histological classification. In contrast, suppressor cell regulation of IgG producing cells was unrelated to the proportion of suppressor/cytotoxic lymphocytes in peripheral blood or HBeAg status, but impaired function was associated with chronic hepatitis, particularly chronic active hepatitis. These data suggest that the increased proportion of suppressor/cytotoxic lymphocytes in the peripheral blood of HBsAg carriers represents an increase in the cytotoxic and not the suppressor cell subset and that this is a consequence of active viral replication and not of the severity of hepatic inflammation. Defective suppressor cell function may be one factor in the development of chronic active hepatitis, but is not reflected by alterations in the T4:T8 ratio. 相似文献
5.
Gennadi V. Glinsky Valeri V. Mossine Janet E. Price Diane Bielenberg Vladislav V. Glinsky Honnavara N. Ananthaswamy Milton S. Feather 《Clinical & experimental metastasis》1996,14(3):253-267
We studied the influence of 10 synthetic glycoamine analogs on colony formation in 0.3 and 0.9% agarose by metastatic human breast carcinoma (MDA-MB-435) and melanoma (TXM-13) cells. Nine synthetic analogs significantly inhibited the colony formation in 0.9% agarose of MDA-MB-435 human breast carcinoma cells; five compounds caused a 73–83% reduction of colony formation. Seven synthetic glycoamines caused a significant inhibition of colony formation in 0.9% agarose by TXM-13 melanoma cells with the inhibitory effect ranging from 71 to 87%. The 50% inhibition (I50) doses and relative activity rank of the compounds were similar for both breast carcinoma and melanoma cell lines. The murine B16 melanoma cell aggregation assay was employed to elucidate the potential mechanism(s) of the inhibitory activity of synthetic glycoamines. The relative activity ranks of the compounds based on the independently determined I50 doses for both cell aggregation and clonogenic growth assays were very similar for the four most active synthetic analogs and clearly indicated the importance of hydrophobic amino acid in mediating the bioactivity of synthetic glycoamines. In both experimental systems (clonogenic growth in agarose and cell aggregation assay) the leading compound was N-(1-deoxy-d-fructos-1-y1)-d-leucine (Fru-d-Leu) and the least active analog was N-(1-deoxy-d-fructos-1-yl)-glycine (Fru-Gly). These results show that synthetic glycoamines may act by competing for specific carbohydrate-lectin interactions, particularly those involving -galactoside-specific lectins expressed on metastatic cells. 相似文献
6.
Nine members, MEL2–MEL10, of the MEL gene family coding for -galactosidase were physically mapped to the ends of the chromosomes by chromosome fragmentation. Genetic mapping of the genes supported the location of all the MEL genes in the left arm of their resident chromosomes. 相似文献
7.
Kinetic and steady-state characteristics of aconitine-modified sodium channels were studied in the Ranvier node membrane. Aconitine-modified sodium channels are shown to be inactivated only partially. The voltage dependence of the fraction of noninactivated channels (h infinity) may be described by a three-state model of the channel with closed, open and inactivated states. A reasonable agreement with the data was obtained when parameters of the inactivated state were supposed to be not changed after aconitine modification of the channels. The membrane repolarization to -70 divided by -110 mV, after long (10 ms) depolarizing shift induces firstly fast current decay ("tail") and then its rather slow increase to a steady-state level. Kinetics of this current requires two or more open states to be postulated. 相似文献
8.
The influence exercised by morphine in a dose of 20 mg/kg, introduced intraperitoneally, and also in concentrations of 10(-3) and 10(-5) "in vitro" on the parameters of oxidative phosphorylation of the brain cortex and stem of rats was studied. Morphine, used in a concentration of 10(-3), is shown to speed up the substrates oxidation rate. During the first days of its administration the narcotic analgetic inhibited oxidation of mitochondia released from the brain stem, and, once habituation to the narcotic had developed, the inhibition ceased to be effective. In "in vivo" experiments and in vitro tests the effect of phosphorylation remained unchanged. The data obtained suggest that with developing habituation in regard to morphine the functions of the brain stem and cortex mitochondria do not undergo any substantial changes. 相似文献
9.
10.
Stepwise surgical tactics by using transsternal transepicardial preocclusion of the main bronchus and lung root vessels, opening of the empyema cavity and pneumotomy has been proposed to treat patients with progressive fibrocavernous tuberculosis complicated by pneumothorax and pleural empyema and extended into the thoracic wall. After 1.5-2 months the main stage of the operation, pleuropulmonectomy, is performed. Among the 25 patients operated on, the clinical effect was achieved in 15, 5 patients continued to take treatment, 5 patients died. The first results show that active care may be delivered to patients with complicated pulmonary and pleural tuberculosis who have recently had no hope to be recovered and the process be steady. 相似文献